I have a new, unreleased app in App Store Connect. The Mac app icon is a rounded rect with transparent border. For some reason, the "Included Assets App Icon" has a black background in App Store Connect. The black background also appears in the TestFlight app. The issue doesn't appear to be specific to the new app's icon, because I tried uploading a build with another icon, from an already released Mac app, and App Store Connect also gave that a black background.
The app icon displays correct at runtime on macOS. The black background is a phenomenon only of App Store Connect and TestFlight. My theory is that App Store Connect is confused and still treating the app icon as if it were iOS rather than Mac. During development, the app has gone through a transition: first it was iOS on Mac, then it was Catalyst, and now finally it's AppKit.
If the App Store Connect record for the app has some kind of iOS or Catalyst flag, I have no idea how to reset the flag. Has anyone else experienced this issue?
